Final answer:
The Soka Gakkai movement split from Nichiren Shoshu due to doctrinal disputes and leadership conflicts. It is criticized for its aggressive proselytizing, leadership cult, and deviations from traditional Buddhism.
Step-by-step explanation:
The movement referred to in this question is most likely the Soka Gakkai, which is a lay Buddhist organization that formed part of the tradition of Nichiren Buddhism. The split within the movement occurred in the early 1990s, when Soka Gakkai was excommunicated by Nichiren Shoshu, the monastic order that had been traditionally associated with it. This separation was largely due to doctrinal disputes, leadership conflicts, and differences in practice.
Criticism of Soka Gakkai has come from various quarters, including religious scholars, former members, and other Buddhist groups. The criticisms often focus on the organization's aggressive proselytizing methods, the personality cult around its leadership, particularly Daisaku Ikeda, and allegations of political and financial irregularities. Some also argue that it has strayed from traditional Buddhist teachings.